Java SWING

Medientechnik
Übung – Java Swing
Heute
•
(GUI-)Programmieren mit Eclipse
•
Java Swing
– Fenster erstellen
– GUI-Komponenten hinzufügen
– Layout-Manager nutzen
Links
http://download.oracle.com/javase/tutorial/uiswing/
http://openbook.galileocomputing.de/javainsel/
http://zetcode.com/tutorials/javaswingtutorial/
Eclipse
•
Programmierwerkzeug (ursprünglich integrierte Entwicklungsumgebung für
Java, mittlerweile auch für viele andere Programmiersprachen)
•
Vorteile:
– Verschiedene Views
– Syntaxhighlighting
– Code Completion
– Code-Folding
– …
•
Shortcuts:
–
Strg+Leertaste: Code Completion
–
Strg+Linksklick auf Funktionsaufruf:
Sprung zur Deklaration der Funktion
–
Cursor über Variable: alle Vorkommen
der Variable werden farbig unterlegt
Eclipse
• Eclipse starten und Workspace festlegen
• Neues Java-Projekt anlegen
• 2 neue Klassen im default-package
erstellen:
– Yaca.java
– View.java
Java – main-Methode
public class Yaca {
public static void main(String[] args) {
View yacaView = new View();
yacaView.setVisible(true);
}
}
Yaca.java
Swing - JFrame
import javax.swing.*;
public class View extends JFrame {
public View() {
this.setTitle(“YetAnotherCalculator”);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
View.java
Swing - JPanel
import javax.swing.*;
public class View extends JFrame {
public View() {
this.setTitle(“YetAnotherCalculator”);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel contentAll = new JPanel();
contentAll.setLayout(new BorderLayout());
}
}
View.java
Swing – JButton
import java.awt.*;
import javax.swing.*;
public class View extends JFrame {
public View() {
[…]
JButton start = new JButton("Start");
JButton clear = new JButton(“Clear");
contentAll.add(start, BorderLayout.SOUTH);
contentAll.add(clear, BorderLayout.SOUTH);
this.setContentPane(contentAll);
this.pack();
}
}
View.java
Swing – JButton
import java.awt.*;
import javax.swing.*;
public class View extends JFrame {
public View() {
[…]
JButton start = new JButton("Start");
JButton clear = new JButton(“Clear");
JPanel contentButtons = new JPanel();
contentButtons.setLayout(new FlowLayout());
contentButtons.add(start);
contentButtons.add(clear);
contentAll.add(contentButtons, BorderLayout.SOUTH);
this.setContentPane(contentAll);
this.pack();
}
}
View.java
Swing – JTextField & JComboBox
import java.awt.*;
import javax.swing.*;
public class View extends JFrame {
public View() {
[…]
JTextField firstInput
JTextField secondInput
JTextField result
String[] methods
JComboBox methodBox
=
=
=
=
new JTextField(5);
new JTextField(5);
new JTextField(5);
{"+", "-", "*", "/"};
= new JComboBox(methods);
this.setContentPane(contentAll);
this.pack();
}
}
View.java
Swing – JTextField & JComboBox
import java.awt.*;
import javax.swing.*;
public class View extends JFrame {
public View() {
[…]
JPanel contentInput = new JPanel(new FlowLayout());
contentInput.add(firstInput);
contentInput.add(methodBox);
contentInput.add(secondInput);
contentInput.add(new JLabel("="));
contentInput.add(result);
contentAll.add(contentInput, BorderLayout.CENTER);
this.setContentPane(contentAll);
this.pack();
}
}
View.java
Swing – default-Werte ändern
import java.awt.*;
import javax.swing.*;
public class View extends JFrame {
public View() {
[…]
firstInput.setText("0");
secondInput.setText("0");
result.setText("-");
result.setEditable(false);
methodBox.setSelectedIndex(2);
this.setContentPane(contentAll);
this.pack();
}
}
View.java
Swing – Window-Position
import java.awt.*;
import javax.swing.*;
public class View extends JFrame {
public View() {
[…]
this.setContentPane(contentAll);
this.pack();
this.setLocation(100, 100);
}
}
View.java